Counterbalanced wedges

ABSTRACT

Described are embodiments of wedge-type golf clubs that include a counterbalance weight located at the butt end of the shaft. The shaft and/or grip of disclosed clubs can have reduced mass while the club head and the butt of the shaft can have increased mass compared to conventional clubs, which provides a similar overall total mass but with an increase in the moment of inertia (MOI). The increase in MOI compared to a conventional club of similar style and mass can provide increased swing stability during a stroke, decreasing unintentional waggling about the hand grip fulcrum. The added weight in the head and the added weight in the butt of the shaft can counterbalance each other so that the overall swingweight of the club can be about the same as for a conventional, non-counterbalanced club having the same total mass, thereby providing a familiar feel and easy playability.

FIELD

This application relates to golf clubs, and more particularly to wedges.

BACKGROUND

Golf is a game in which a player, choosing from a variety of differentgolf clubs, seeks to hit a ball into each hole on the golf course in thefewest possible strokes. A wedge is one type of golf club, and isdesigned for hitting short, precise shots onto a green, hittinghigh-lofted shots, and for hitting shots from difficult lies, such asfrom tall grass or from a sand bunker. In some wedge shots, the head ofa wedge may travel through turf, sand, or other materials prior tostriking the ball. When swinging a wedge, it is desirable to maintain asmooth, stable stroke to provide optimal accuracy and precision.

SUMMARY

Described below are embodiments of wedges and other iron-type golf clubsthat are counterbalanced with significant mass located near the butt ofthe shaft above the grip location. Additional mass may also be added tothe club head compared to a conventional club head. In the disclosedgolf clubs, the club head and the butt end of the club can haveincreased mass compared to an analogous conventional club, whichprovides an increase in overall total mass, an increase in the moment ofinertia about the CG of the club (MOI_(CG)), while maintaining a balanceabout the hand grip fulcrum location that provides a similar swingweightcompared to a conventional club. The increase in club head mass andMOI_(CG) compared to a conventional club of similar style can provideincreased swing stability during a stroke, decreasing unintentionalwaggling about the hand grip fulcrum, and thus providing increasedaccuracy and precision to wedge shots. The increase in club head massand MOI_(CG) can also help the club head travel through soil, grass,sand, etc., with more momentum and less interruption, providing moreconsistent and accurate ball striking. The familiar swingweight of thedisclosed clubs compared to conventional clubs makes the disclosed clubfeel familiar to a golfer and therefore the disclosed clubs can bereadily playable in place of a conventional club without the golferhaving to significantly change his swing.

The foregoing and other objects, features, and advantages of thedisclosed technology will become more apparent from the followingdetailed description, which proceeds with reference to the accompanyingfigures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a conventional wedge-type golf club.

FIG. 2 shows an exemplary wedge-type golf club having a counterbalanceweight positioned at the butt end of the club.

FIG. 3 is a cross-sectional view of a butt end of an exemplary clubhaving a counterbalance weight positioned at the top end of a hand gripand having a radial outer surface that is substantially contiguous witha radial outer gripping surface of the hand grip.

FIG. 4 is a cross-sectional view of a butt end of another exemplary clubhaving a counterbalance weight positioned within the top end of the handgrip and secured to the top end of the shaft.

FIG. 5 shows a wedge-type golf club at a point in a swing just prior tostriking a ball or contacting the ground behind the ball.

FIG. 6 shows the wedge-type golf club at a point in the swing aftertravelling through the ground behind the ball and just after striking aball.

FIG. 7 is a graph that illustrates displacement in the ground directionas a function of time for two different wedge-type golf clubs from thetime they club head contacts the ground to a time after the club headlifts above the ground.

DETAILED DESCRIPTION

Disclosed herein are embodiments of wedges and other golf iron-typeclubs that are counterbalanced with a counterbalance weight located ator near the upper end or “butt end” of the shaft above the grippinglocation. As used herein, the terms “wedge” and “wedge-type golf club”mean any iron-type golf club having a static loft angle that is greaterthan 45°. Any of the disclosure described herein in relation to a wedgeor wedge-type golf club can be embodied in any of various wedges havingdifferent loft angles, such as a pitching wedge, gap wedge, sand wedge,lob wedge, flop wedge, and/or wedges having static loft angles of 46°,48°, 50°, 52°, 54°, 56°, 58°, 60°, greater than 60°, and any otherangles greater than 45°. The disclosed technology can also be embodiedin iron-type golf clubs having static loft angles of 45° or less, suchas a 9-iron or lower-numbered irons.

In disclosed embodiments, the club head and the butt end of the shafthave increased mass compared to a conventional club of the same loft andstyle. Such clubs can have an increased overall total mass as comparedto a conventional club of similar type, and can have an increase in themoment of inertia (MOI) of the club about the CG and/or about the handgrip fulcrum location (e.g., where the club pivots when a golfer rotateshis hands/wrists). The increase in MOI can provide increased swingstability during a swing stroke, decreasing unintentional waggling aboutthe CG and hand grip fulcrum, and thus providing increased accuracy andprecision to shots. In addition, the increase in MOI, and in particularthe increase provided by the added mass in the club head, can providegreater momentum and stability as the club head travels through turf,sand, or other material, leading to less disruption of the path,orientation, and velocity of the club head.

At the same time, the added weight in the club head and the added weightin the butt end of the shaft can counterbalance each other in such a waythat the overall swingweight of the club (e.g., rotational moment aboutthe hand grip fulcrum location due to gravity) can be about the same asfor a conventional, non-counterbalanced club having significantly lesstotal mass. Having the same or similar swingweight can provide thegolfer a familiar feel and sensation during a swing that makes thedisclosed clubs readily playable in place of a conventional club withouthaving to adjust one's swing.

Club Length Dimensions

FIG. 1 shows a conventional wedge-type golf club 10 and illustrates anexemplary methodology for measuring club length dimensions based on thecenter of gravity (CG) and other features of the club. Club 10 has ashaft 14 that couples its grip 16 to its head 12. The overall shaftlength (L₁) of the club 10 can be measured from a point 18 where theshaft center axis intersects the bottom/sole of the head 12 to the buttend 20 of the club. A dimension “d₁” can be defined as the distance fromthe CG to the lower shaft axis intersection point 18 and a dimension“c₁” can be defined as the distance from the CG to the butt end 20 ofthe club.

Club Swingweight

FIG. 1 also illustrates a methodology for calculating the swingweight ofa golf club. The club 10 has a hand grip fulcrum point 22, which is anapproximation of the pivot point about which a club pivots when a golferholding the club rotates his hands/wrists. The fulcrum point 22 can bedefined as being a predetermined distance “e” from the lower shaft axisintersection point 18 along the shaft axis. For example, the distance“e” can be defined as 30 inches. The swingweight of the club can then bedefined as the moment about the fulcrum point 22 caused by gravity whenthe club is horizontal and fixed at the fulcrum point. This swingweightmoment “M_(e)” can be calculated as the product of the gravitationalforce “Fab” multiplied by the distance from the CG to the fulcrum point22, which is equal to the distance “e” minus the distance “d₁”. F_(club)is equal to the total mass “m” of the club multiplied by thegravitational constant “g”. Thus, M_(e)=(e−d₁)*m*g. Accordingly,changing the total mass of a club and/or shifting the location of the CGalong the shaft axis (changing the distance “d₁”) can change theswingweight of the club and cause the club to feel different when heldand during a swing. Thus, it can be desirable to provide a club thatmaintains a similar swingweight compared to conventional clubs such thata golfer is provided with a familiar feel and sensation when switchingto a new club. In some embodiments, the swingweight can be maintained ata similar level when additional mass is added to the club by increasingthe mass at the butt end of the club, which shifts the CG toward thebutt end of the club and increases d₁, thereby counterbalancing asmaller amount of mass added to the club head.

Club MOI

The moment of inertia (MOI) of a wedge or other iron-type golf club canbe determined based on a selected axis perpendicular to the shaft. TheMOI about a given axis provides a measure of the club's inertialresistance to rotating about that axis. For example, the MOI of the club10 about an axis extending perpendicular to the shaft axis (e.g.,perpendicular to the page in FIG. 1) and passing through the CG of theclub is referred to as the “MOI_(CG)” of the club 10. Similarly, the MOIof the club 10 about an axis extending perpendicular to the shaft axisand passing through the grip fulcrum point 22 is referred to as the“MOI_(e)” of the club.

Calculating the true MOI of a club about any axis can be difficult. Onemethod of calculating the MOI of a club about a selected axis is bymeasuring the undamped period of oscillation of the club while it isfixed to a torsional spring of a testing machine at a point where theselected axis intersects the shaft axis, with the torsional spring beingaligned with the selected axis. The overall MOI of the system (club plustorsional spring fixture) can then be calculated using the formulaMOI=(k*T²)/(4π²), where “k” is the coefficient of the torsional spring,and T is the undamped period of oscillation of the whole system. The MOIof the club about the selected axis is then equal to the overall MOI ofthe system minus the MOI of the torsional spring fixture by itself.Thus, the MOI of the club about the selected axis can be calculated asMOI_(club)=(k/4π²)*(T²−(T_(fixt))²), where “T_(fixt)” is the period ofoscillation of the torsional spring fixture by itself without a clubfixed to it. T_(fixt) can be a known value for a given MOI testingsystem. Using such a testing system and method, the MOI of the clubabout any axis intersecting the shaft can be calculated, such as theMOI_(CG) or the MOI_(e).

MOI values for a club can also be approximated, such as by assuming themass of the shaft and grip are negligible and representing the club headas a point mass at the center of the head. The MOI about a given axisperpendicular to and intersecting the shaft axis can then beapproximated as the mass of the club head multiplied by the square ofthe distance from the center of the head to the given axis. This isillustrated in FIG. 1 for the club 10. The club head 12 has a center 24(e.g., CG of the head or geometric center of the head, etc.) and thedistance from the center 24 to the grip fulcrum point 22 is shown as“X₁”, such that the MOI_(e) of the club 10 about the grip fulcrum axis22 can be approximated as the mass “N₁” of the head 12 multiplied by thesquare of the distance “X₁”, or N₁*X₁ ².

Exemplary Counterbalanced Clubs

FIG. 2 shows an exemplary counterbalanced wedge-type golf club 50 thatcomprises a head 52, a shaft 54, a grip 56, and a counterbalance weight57 at or near the butt end of the club. The overall length “L₂” of theclub 50 is measured from the lower shaft axis intersection point 58 tothe butt end 60 of the club, which can be the end of the counterbalanceweight 57. The MOI_(CG) of the club 50 can be increased due the presenceof the counterbalance weight 57 and/or additional mass added to the clubhead. The MOI_(e) of the club 50 about the fulcrum point 62 can also beincreased. Note that the fulcrum point 62 is the same predetermineddistance e (e.g., 30 inches) from the lower shaft axis intersectionpoint 58 as in the conventional club 10.

The MOI_(e) of the club 50 can be approximated as the sum of theinertial effect of the head 52 and the inertial effect of thecounterbalance weight 57. As described above, the inertial effect of thehead 52 can be approximated as N₂*X₁ ², where “N₂” is the mass of thehead 52. Similarly, the inertial effect of the counterbalance weight 57can be approximated as N₃*X₂ ², where “N₃” is the mass of thecounterbalance weight 57 and “X₂” is the distance from the center 66 ofthe counterbalance weight to the grip fulcrum point 62, as shown in FIG.2. Thus, the MOI_(e) of the club 50 can be approximated as the sum of(N₂*X₁ ²)+(N₃*X₂ ²).

The MOI_(CG) of the club 50 can be approximated in a similar mannerusing analogous dimensions from the mass centers 64 and 66 to the CG.The MOI_(e) and MOI_(CG) of the club 50 will therefore be greater thanthe MOI_(e) and MOI_(CG) of the club 10 if the mass of their heads areequal or if the mass of the head 52 of club 50 is greater than the massof the head 12 of club 10. The greater MOI_(e) and/or greater MOI_(CG)of the club 50 can provide greater swing stability during a swing andcan make it more difficult for a golfer to accidentally adjust the swingpath of the club when it is in motion, giving the golfer moreconsistent, predictable ball striking. This also gives the club headmore inertial resistance while traveling through turf, sand, or othermaterial prior to striking the ball, thereby maintaining swing speed andswing path.

While an increase in MOI_(e) and/or MOI_(CG) is desirable, it can alsobe desirable to increase the mass of the club head and/or maintain thesame or similar swingweight compared to a conventional club 10. To addmass to the club head 52 and add mass to the butt end of the club in theform of the counterbalance weight 57, it may be desirable to subtractmass from elsewhere in the club so the club does not become too heavyand feel awkward to the golfer. For example, the mass of the shaftand/or the mass of the grip can be reduced to accommodate the added massof a counterbalance weight and the added mass in the club head. In someembodiments, a lightweight shaft can be used instead of a conventionalshaft. For example, the shaft can comprise substantially all graphiteand/or other lightweight materials. In another example, a bi-matrixshaft can be used that comprises graphite and/or other lightweightmaterial in an upper portion and steel and/or other strong, plasticallydeformable material in a lower portion or tip portion to allow the tipportion to be plastically bent to adjust the orientation of the headrelative to the shaft axis. The grip can also be comprised oflightweight material and/or can be reduced in volume to reduce its masscontribution to the club. By reducing the mass of the shaft and/or grip,more mass can be added to the club head and counterbalance weightwithout making the club overly heavy.

The counterbalance weight 57 can comprise any dense material, can haveany shape, and can be coupled to the shaft and/or grip in any manner. Insome embodiments, the counterbalance weight can be adjustable and/orremovable. In some embodiments, two or more counterbalance weights canbe provided to allow a user to select which one to couple to the club.For example, the different counterbalance weights can have differentmasses, different shapes, different lengths, and/or different aestheticappearances. A person may be able to remove one weight from the shaftand attach another weight to the shaft to change the characteristics ofthe club. In some embodiments, two or more counterbalance weights may beattached to the club at the same time, such as one on top of the otheror side-by-side, etc. For example, a first weight may attach to theshaft and a second weight may attach to the first weight. In someembodiments, the different weights can appear identical, but havedifferent masses (e.g., different materials and/or hollow regions). Insome embodiments, the counterbalance weights can require a tool to beremoved from the club or to be secured to the club, while in otherembodiments no tool is required. When attached to the club, thecounterbalance weights may be non-adjustable or may be adjustable.

In embodiments where a counterbalance weight is adjustable when attachedto the club, the axial position of the counterbalance weight relative tothe shaft and/or grip may be adjusted. For example, the counterbalanceweight may be adjustable along the shaft axis by rotating thecounterbalance weight relative to the shaft. A threaded attachment withthe shaft may be used, for example. In some embodiments, the positionaladjustability can be limited to a group of discrete positional settings,rather than a continuous or analog range of positions. In suchembodiments, the weight can be fixable at each of the discretepositional settings, such as by using a tool to tighten a set screw, orthe like.

FIGS. 3 and 4 are cross-sections of exemplary butt ends of clubs thatinclude a counterbalance weight. FIG. 3 shows a club 70 that comprises ashaft 72, a grip 74 mounted around the top end of the shaft, and anexternal counterbalance weight 76 mounted around the top end of thegrip. In this example, the grip 74 includes a thin or narrowed upper anda top portion 82 that extends around the top end of the shaft 72. Thecounterbalance weight 76 has a recess that receives the upper portion 80and top portion 82 of the grip. The counterbalance weight 76 can have atop portion 84 that covers the top portion 82 of the grip and forms theupper surface of the club 70. The grip can be secured to the shaft withan adhesive or other means, and the counterbalance weight can be securedto the grip with an adhesive or other means.

A counterbalance weight can have a radial outer surface that issubstantially contiguous with and/or blends into the radial outergripping surface of the grip, such that a smooth transition is formed atan annular joint 78 (see FIG. 3) between the radial outer surfaces ofthe grip and the weight. In some embodiments, the appearance of the gripand the weight can be similar such that the transition at the joint 78is minimally noticeable visually or tactiley, while in otherembodiments, they may have different colors or finishes such that thetransition at the joint 78 is visually noticeable but minimallynoticeable by feel. As shown in FIG. 3, the counterbalance weight mayincrease in diameter or width moving upwardly from the joint 78. Thiscan provide more volume and mass per vertical length of thecounterbalance weight.

FIG. 4 is a cross-sectional side view of the butt end of anotherexemplary club 90 that has an internal counterbalance weight 96. Theclub 90 comprises a shaft 92, the counterbalance weight 96 mounted tothe top end of the shaft, and a grip 94 mounted around the top end ofthe shaft and covering the counterbalance weight, including a grip topportion 100 positioned over the top of the weight 96. The weight 96includes a lower portion 98 that is inserted into and secured to the topend of the shaft, such as by threads, friction fit, welding, adhesive,etc. In this embodiment, substantially the entire outer surface of thebutt end of the club 90 is provided by the grip 94. The weight 96 canhave about the same diameter as the shaft 92, such that the weighteffectively extends the length of the shaft.

In any of the embodiments disclosed herein, the counterbalance weightcan have any axial length, provided the width and density of it aresufficient to provide the desired mass addition to the butt end of theclub. In some circumstances, it may be undesirable for the butt end of aclub to extend too far above the golfer's hands. For example, rules mayprohibit the butt end of the club from contacting or being anchored tothe golfer's torso or other body portion other than the hands. Further,the butt end of the club may undesirably contact the golfer's legs orother body part during a swing if it projects too far above the golfer'shands. Thus, a shorter counterbalance weight can be desirable. Toprovide a maximum mass per axial length added to the club, thecounterbalance weight can be made wider (e.g., as wide as the grip orwider) and can be made from a relatively dense material, such as steel,tungsten, or other dense metals. In some embodiments, the axial lengthof the counterbalance weight is less than four inches, less than 3inches, less than 2 inches, and/or less than 1 inch. The overall length“L₂” of a counterbalance wedge-type clubs as described herein includinga counterbalance weight can be less than or equal to 40 inches, lessthan or equal to 39 inches, less than or equal to 38 inches, less thanor equal to 37 inches, and/or less than or equal to 36 inches.

The mass added to the club head 52 can be added in any manner. In someembodiments, one or more adjustable and/or removable weights can becoupled to the club head. Such weights may be removable andinterchangeable with other weights having different masses. In otherembodiments, the size and/or materials of the club head may be changedto increase the mass of the club head a desired amount.

The disclosed counterbalanced clubs can have any overall mass, though insome embodiments the overall mass of the club, including any weights,can be at least about 400 grams, at least about 450 grams, at leastabout 475 grams, at least about 500 grams, and/or at least about 525grams.

The counterbalance weight(s) itself can also have any mass, though insome embodiments the mass of the counterbalance weight is at least about25 grams, at least about 40 grams, at least about 50 grams, at leastabout 70 grams, and/or at least about 100 grams.

The mass of the club head can be, for example, at least about 280 grams,at least about 300 grams, at least about 310 grams, at least about 320grams, and/or at least about 340 grams.

The mass added to the club head, whether in the form of one or moreweights movable relative to the head body or increased mass of the headbody, can be at least 5 grams, at least 8 grams, at least 10 grams,and/or at least 15 grams. In one particular example, the club head has atotal mass of about 309 grams, including added mass in the form of oneor more weights that have a mass of about 9 grams, while thecounterbalance weight has a mass of about 50 grams.

The shaft can have any mass, such as 130 grams or less, 100 grams orless, 80 grams or less, 70 grams or less, and/or 60 grams or less. Inone particular example, a bi-matrix shaft is included that has agraphite upper portion with a mass of about 50 grams and a steel lowerportion with a mass of about 20 grams, providing a total of about 70grams.

The grip can also have any mass, such as 100 grams or less, 50 grams orless, 40 grams or less, and/or 35 grams or less. In some embodiments,the grip comprises a lightweight EVA material.

The total mass of the shaft and grip together can be lower than in aconventional club, such as less than 200 grams, less than 150 grams,less than 125 grams, less than 110 grams, and/or less than 100 grams.

The disclosed counterbalance clubs can have any MOI_(CG), such as atleast 500 kg*cm², at least 525 kg*cm², at least 550 kg*cm², at least 575kg*cm², at least 600 kg*cm², and/or at least 625 kg*cm². Similarly, thedisclosed counterbalance clubs can have any MOI_(e) (with e=30 inches),such as at least 2000 kg*cm², at least 2025 kg*cm², at least 2050kg*cm², at least 2075 kg*cm², at least 2100 kg*cm² and/or at least 2200kg*cm².

Another meaningful parameter type for counterbalanced golf clubs areratios of a club moment of inertia divided by the club length squared(L²). For example, the ratio MOI_(CG) per unit length² (in units ofkg*cm²/inch²) for the disclosed counterbalance clubs can be from about1.4:1 to about 1.1:1, from about 1.35:1 to about 1.15:1, and/or fromabout 1.3:1 to about 1.2:1.

Yet another meaningful parameter for counterbalanced golf clubs areratios of a club moment of inertia divided by the total club mass. Forexample, the ratio MOI_(CG) per unit mass (in units of kg*cm²/g) for thedisclosed counterbalance clubs can be at least 1.05, at least 1.10, atleast 1.15, at least 1.20, and or at least 1.23.

Still another meaningful parameter type for counterbalanced clubs is theratio of the MOI_(CG) per unit length² divided by the total club mass.This parameter can be expressed in terms of a unitless percentage andcan be referred to as “inertial efficiency” since it represents howeffectively the mass and length of the club are utilized to maximize theMOI_(CG). The disclosed counterbalance clubs can have an inertialefficiency of at least 13%, at least 13.3%, at least 13.5%, at least13.8%, at least 14.0%, at least 14.2%, at least 14.4%, at least 14.6%,at least 14.8%, and/or at least 15.0%.

The disclosed counterbalance clubs can have a swingweight that issimilar to a conventional club of the same type having less mass. Forexample, the disclosed counterbalance clubs can have a swingweight (withe=30 inches) of less than 3.0 N*m, less than 2.8 N*m, less than 2.7 N*m,greater than 2.6 N*m, greater than 2.64 N*m, greater than 2.68 N*m,between 2.5 N*m and 3.0 N*m, between 2.6 N*m and 2.8 N*m, between 2.63N*m and 2.75 N*m, and/or between 2.66 N*m and 2.70 N*m.

Table 1 below provides representative data for two different exemplarywedges. Wedge A is an exemplary embodiment of the counterbalanced clubsdescribed herein, having a 58° loft. Wedge B is an exemplaryconventional wedge having the same 58° loft and same general style asWedge A, but without a counterbalance weight at the butt end of theshaft and less club head mass. As shown in Table 1, Wedge A is slightlylonger than Wedge B due to the counterbalance weight added to the buttend of the shaft. Wedge A also has a greater mass, greater MOI_(CG), andgreater inertial efficiency than Wedge B. However, Wedges A and B haveabout the same swingweight.

TABLE 1 Sole- MOI_(CG) per Inertial Length to-CG Mass MOI_(CG) Unit MassEfficiency Swingweight Wedge (in) (in) (g) (kg * cm²) (kg * cm²/g)(unitless) (N * m) A 35.75 9.50 527 647 1.23 14.9% 2.693 B 35 7.55 471489 1.04 13.2% 2.632

Ground Interaction

FIGS. 5 and 6 illustrate the interaction of an exemplary wedge 100 withthe ground 104 during a swing prior to and just after striking a ball102. FIG. 5 shows the head of the wedge 100 just prior to contacting theground 104, while FIG. 6 shows the head of the wedge 100 contacting theball 102 after traveling through a section of the ground 104.

FIG. 7 is a graph showing the depth of the lower surface of the head ofthe wedge 100 below the surface of the ground 104 as a function of time,for an exemplary 58° counterbalanced wedged (dashed line) and for aconvention 58° wedge of the same general style (solid line), eachtraveling at 80 mph club head speed relative to the ground. The data inFIG. 7 was generated using a simulation method wherein the ground modelis simulated using smoothed particle hydrodynamics to represent softsand, wherein the solid mesh turns into particles when the solid meshreaches 0.01 strain and thereafter the particles interactions aremodeled. In the simulation, the counterbalanced wedge includes anadditional 40 gram counterbalance weight located 0.5 inches above thebutt end of the shaft (where the conventional shaft ends) and anadditional 10 grams of mass added to the club head compared to theconvention club head (via increased density), with the same size clubhead in both wedge models. The same velocity conditions were used withboth wedge models.

As shown in FIG. 7, the counterbalanced wedge digs further below thesurface of the ground (about 10 mm, compared to about 9 mm for theconventional wedge), which illustrates that the counterbalanced wedgehas more downward momentum and is less impeded by the ground. Inaddition, the counterbalanced wedge rebounds from the lowest pointquicker than the conventional wedge and also exits the ground(displacement >0) slightly sooner than the conventional wedge, againillustrating less disruption from the ground. Because thecounterbalanced wedges as disclosed herein have greater inertia andsuffer less disruption from the ground prior to striking the ball,compared to conventional wedges, the counterbalanced wedges provide moreconsistent, accurate ball striking and maintains a greater velocitywhile traveling through the ground, leading to greater shot distances.

Exemplary Materials

The components of the embodiments disclosed herein can be formed fromany of various suitable metals, metal alloys, polymers, composites, orvarious combinations thereof.

In addition to those noted elsewhere herein, examples of metals andmetal alloys that can be used to form the components include, withoutlimitation, carbon steels (e.g., 1020 or 8620 carbon steel), stainlesssteels (e.g., 304 or 410 stainless steel), PH (precipitation-hardenable)alloys (e.g., 17-4, C450, or C455 alloys), titanium alloys (e.g., 3-2.5,6-4, SP700, 15-3-3-3, 10-2-3, or other alpha/near alpha, alpha-beta, andbeta/near beta titanium alloys), aluminum/aluminum alloys (e.g., 3000series alloys, 5000 series alloys, 6000 series alloys, such as 6061-T6,and 7000 series alloys, such as 7075), magnesium alloys, copper alloys,nickel alloys, and tungsten.

Examples of composites that can be used to form the components include,without limitation, glass fiber reinforced polymers (GFRP), carbon fiberreinforced polymers (CFRP), metal matrix composites (MMC), ceramicmatrix composites (CMC), and natural composites (e.g., wood composites).

Examples of polymers that can be used to form the components include,without limitation, thermoplastic materials (e.g., polyethylene,polypropylene, polystyrene, acrylic, PVC, ABS, polycarbonate,polyurethane, polyphenylene oxide (PPO), polyphenylene sulfide (PPS),polyether block amides, nylon, and engineered thermoplastics),thermosetting materials (e.g., polyurethane, epoxy, and polyester),copolymers, and elastomers (e.g., natural or synthetic rubber, EPDM, andTeflon®).

In view of the many possible embodiments to which the principles of thedisclosed technology may be applied, it should be recognized that theillustrated embodiments are only examples and should not be taken aslimiting the scope of the disclosure. Rather, the scope of thedisclosure is at least as broad as the following exemplary claims. Wetherefore claim all that comes within the scope of the following claims.

1. A wedge-type golf club comprising: a club head having a static loftangle greater than 45°; a shaft having an upper end and a lower end thatis coupled to the club head; a hand grip coupled to the shaft betweenthe upper end and the lower end; and a counterbalance weight coupled tothe upper end of the shaft, the counterbalance weight having a mass ofat least 40 grams; wherein the golf club has a total mass of at least500 grams, a total length of from about 35 inches to about 38 inches, anMOI_(CG) of at least 600 kg*cm², and an inertial efficiency of at least13.5%, wherein inertial efficiency is a unitless ratio of the MOI_(CG)per unit length squared divided by the total club mass.
 2. The golf clubof claim 1, wherein the golf club has an inertial efficiency of at least14.8%. 3-5. (canceled)
 6. The golf club of claim 1, wherein thecounterbalance weight has a mass of at least 50 grams.
 7. The golf clubof claim 1, wherein the golf club has a swingweight that is between 2.6N*m and 2.8 N*m.
 8. The golf club of claim 1, wherein the counterbalanceweight is removably coupled to the upper end of the shaft, or ispositionally adjustable relative to the shaft.
 9. (canceled)
 10. Thegolf club of claim 1, wherein the hand grip has an outer grippingsurface and the counterbalance weight has an outer surface, and thecounterbalance weight is positioned above the hand grip such that theouter surface of the counterbalance weight is substantially contiguouswith the outer gripping surface of the hand grip.
 11. The golf club ofclaim 1, wherein the shaft comprises a bi-matrix shaft that comprisesgraphite material in an upper portion of the shaft and steel in a lowerportion or tip portion of the shaft.
 12. A wedge-type golf clubcomprising: a club head having a static loft angle greater than 45°; ashaft having an upper end and a lower end that is coupled to the clubhead; a hand grip coupled to the shaft between the upper end and thelower end; and a counterbalance weight coupled to the upper end of theshaft separate from the grip; wherein the counterbalance weight has amass of at least 40 grams; and wherein the golf club has a total mass ofat least 500 grams, a total length of from about 35 inches to about 38inches, an MOI_(CG) of at least 600 kg*cm², and a swingweight that is ina range from about 2.5 N*m to about 3.0 N*m.
 13. The golf club of claim12, wherein the couterbalanance weight has a mass of at least 50 grams.14. The golf club of claim 12, wherein the golf club has a swingweightthat is in a range from about 2.6 N*m to about 2.8 N*m.
 15. (canceled)16. The golf club of claim 12, wherein the golf club's total mass isbetween 500 grams and 600 grams.
 17. The golf club of claim 12, whereinthe counterbalance weight is removably coupled to the upper end of theshaft, or is positionally adjustable relative to the shaft.
 18. The golfclub of claim 12, wherein the club head has a total mass of between 300grams and 320 grams.
 19. The golf club of claim 12, wherein the handgrip has a radial outer gripping surface and the counterbalance weighthas a radial outer surface, and the counterbalance weight is positionedabove the hand grip such that the radial outer surface of thecounterbalance weight is substantially contiguous with the radial outergripping surface of the hand grip.
 20. The golf club of claim 12,wherein the shaft comprises a bi-matrix shaft that comprises graphitematerial in an upper portion of the shaft and steel in a lower portionor tip portion of the shaft.
 21. The golf club of claim 1, wherein theclub head has a total mass of between 300 grams and 320 grams.
 22. Thegolf club of claim 21, wherein the hand grip and the shaft have acombined mass of 150 grams or less.
 23. The golf club of claim 18,wherein the hand grip and the shaft have a combined mass of 150 grams orless.
 24. A wedge-type golf club comprising: a wedge-type club headhaving a static loft angle greater than 45°; a shaft having an upper endportion and having a lower end portion that is coupled to the club head;a hand grip coupled to the upper end portion of the shaft, the hand griphaving a lower hand grip portion positioned around the shaft and anupper hand grip portion that is positioned around the upper end portionof the shaft, wherein the upper hand grip portion has an outer diameterthat is smaller than an outer diameter of the lower hand grip portion;and a counterbalance weight positioned around the upper hand gripportion of the hand grip and positioned above the lower hand gripportion, the counterbalance weight having a greater density than thehand grip and the shaft; wherein the lower hand grip portion has aradial outer gripping surface and the counterbalance weight has a radialouter surface, and the counterbalance weight is positioned above theradial outer gripping surface such that the radial outer surface of thecounterbalance weight is substantially contiguous with the radial outergripping surface of the lower hand grip portion.
 25. The wedge-type golfclub of claim 24, wherein the counterbalance weight increases indiameter from a lower end of the counterbalance weight to an upper endof the counterbalance weight.
 26. The wedge-type golf club of claim 24,wherein the upper hand grip portion extends at least partially over theupper end of the shaft, and the counterbalance weight extends at leastpartially over an upper end of the upper hand grip portion.